Damper control



May 18, 1948. T. F. DUIS ETAL DAMPER CONTROL Filed April 19, 1945 k 2% mm Patented May 18, 1948 DAMPER CONTROL Troy F. Duis and William'H.Moerchen,

Streator, Ill.

Application April 19, 1945, Serial No. 589,232

. 1 This invention relates to a damper and to an automatic controltherefor. It has for one object to provide an automatic damper controlwhich will operate in response to one or more variable conditionspresent in a furnace when combustion is occurring.

It has for another object to provide a damper control for use inconnection with furnaces to which forced air is supplied and to causethe damper control to operate in response to variations in'the supply ofair.

Another object is to provide a damper control arranged to operate inresponse to variations in suction conditions within the smoke pipe ofthe furnace.

Another object is to provide means for operating a damper control inresponse to variations in the air supply to the furnace and in responseto variations of conditions in the smoke pipe of the furnace. v

Other objects will appear from time to time throughout the specificationand claims.

. This invention is illustrated more or less diagrammatically in theaccompanying drawings, wherein: I i 7 Figure 1 is a diagrammatic sideelevation'illustrating one form of the device;

Figure 2'is a detailed frontelevation on an enlarged scale, showinga'latching mechanism;

Figure 3 is a sectional detail showing a modified form of pistoncontrolling means; and

Figure 4 is a sectional detail showing a further modified form of pistoncontrolling means.

Like parts are indicated by like characters throughout the specificationand the drawings.

The invention, as shown, is illustrated diagrammatically in associationwith a furnace or combustion device and a blower or air-supplying means.As shown, the furnace is indicateddia grammatically at I. The inventionmay be applied to almost any type of burning device. A smoke pipe 2conducts away the smoke and gases which result from the combustion.

A blower 3 is associated with the furnace, which forces air to thefurnace. The blower may also be associated with the means for supplyingfuel, but these are not shown herewith, as they form no essential partof the present invention, which may be applied to a furnace burningsolid or liquid fuel, a

A damper 4 is fixed on a shaft 5, which is pivoted in the smoke pipe 2.A lever or arm 6 is also fixed on the shaft and arranged to tilt thedamper, A counterweight 1 may be adjustably 12 Claims. (Cl. 236-15) 7end. At the opposite end the arm may be perfe rated,as at 8, orotherwise shaped to receive one end of a chain 9. The chain is alsopreferably provided with a ring or hook-engaging means l0. Below thering a cable Il may extend through a cylinder head I2 of a cylinder I3which has a closed bottom 14. The cable is fixed within the cylindertoapiston l5. r a

Air'from the blower 3 moves through a pipe or conduit I6 into'the upperend of the cylinder l3, as shown in Figure 1. A pipe or conduit [1 isconnected, as at I8, to the interior of the cylinder 13 and isconnected, as at Hi, to the interior of the smoke pipe 2. A stop 20 maybe adjustably fixed upon the cable to limit the downward movement of thepiston. I

Asthe means for locking the damper in the open position, the ring In isarranged to be engaged. over a hook 2|. This hook may be carried on asupport 22 mounted on the front of the furnace or boiler. As will beseen from Figure 2, the hook 2| is offset from the normally verticalpositionofthechain, j

In Figure 3, instead of the piston and cylinder mechanism of Figure 1, acylinder 23 having a head and a closed bottom 25 may be used. Thiscylinder has mounted within it a closed bellows 26. The cable II passesthrough the cylinder head 24 and is secured to the bellows. The pressureconduit I6 is in communication with the cylinder 23, as at 2|,"and thesuction conduit I! is in communication with the interior of thebellows,asat28.' Y

In the modified construction of Figure 4. a'cylinder 29 is used. Thiscylinder has. a cylinder head 30 through which the cable ll passes. Ithas a closed bottom 3| It is'partially filled with a liquid .32. Aninverted cup 33 is positioned within the cylinder 29 andfloats in theliquid 32. The cable II is secured to the inverted cup; The pressureconduit l 6 is incommunication with the cylinder 29, as at 34, and thesuction conduit I I is vin communication withfthe interior of theinverted cup 33,asat35'. V p Although we. have shown an operative formof our invention, itwill be recognized that many changes in the form;shape and arrangement of parts can be made without departing from thespirit of the invention, and ur showing is therefore to be taken as, ina sense, diagrammatic.

.The use and operation of this invention are asfollows:

The control is associated with a fuel burning device which forpurposesof simplicity has been positioned on the arm 6, preferablyadjacent one called a furnace, although it might be associated 3 with astove or any equivalent means in which fuel is burned and in connectionwith which means are provided for furnishing air from a blower or itsequivalent.

In any combustion device the products of combustion are discharged, andfor purposes of simplicity the means or opening through which they aredischarged is referred to as a smoke pipe. some suction is produced inthe smoke pipe. The device, whether it includes the cylinder of Figurel, the bellows of Figure 3 or the dash-pot of accidentally engaged uponit.

Figure 4, operates in substantially the same man ing the parts willstand in substantially the posig tion shown in full. lines in Figure 1.

ing and the blower is inactive. Assumingnow When the fire under thefurnace is not u m- They will also stand in this position when the noisburn 1 Should the chain,,the cable or other associated partsxbreak, thecounterweight i will overbalance V the opposite endof the arm 6 and willcarry the cated in dotted lines in Figure 1. The degree to damper '4 toan open position such as that indiling-damper may bemoved in thisdirection that combustion is taking place and that the lower isoperating, air under pressure will be supplied through the conduit. 16.to the cylinder above the piston, the bellows'or thei dashepot. For someinstallations thev connection i! from the cylinder to the. smoke. pipeWill be omitted.

Assuming for the present that the conduit I] is as shown in Figure, 1,when combustion takes place, suction is, developed in the smoke pipe andhence suction is effective in the cylinder below the piston or thedash-pot or from within the bellows. Where these. twov forces are ineffect, pressure from the. blower and suction from the smoke pipe movethe member to which the cable ll is'secured downwardly, and thus.theilever B is .rotated from the full lineposition of; Figure 1 -and thedamper is progressively opened-,, When suction in the smoke pipe isreduced andfthc sup.- ply of air from the. blower is reduced, the pistonrises and the lever B rotates,in'counterclockwise direction under 'theinfluence thepzcolmter- Weight, I. Sincethe. .piston'orthe equivalentmembers as shown in Figures. 321111111 are moved; as'a combined resultof'variationsin, suction in the escape of, air-from below the. piston.or from.

within the bellows or from below theJdash-pot1'33.v

Where that is thecase and;

must .be provided. In the casejof the structure of Figure l, the closureplate i l. for the cylinder! 63 would'be omitted. In the case 'of. theform of:

Figure 3 an opening'tlo the air. would beprovided. from below thebellows and in the case of Figure i is moved somewhat tothe side fromthe verticalline along which'it will: ordinarilymove during operationofthe deviceand-is engaged uponthe.

hook 2]. Should an operator, halvingengaged the hook andring, forget todisengage them, they will become automatically disengaged inthefollowing manner: Assume that the ring H] is engaged upon th'e hook2land-that the apparatus is in operation. .Sooner or later. sufiicien tsuction: or sufficient airpressure or both .will be effectiveshould the"chain be broken depends of course upon the clearance available formovement of the lever arm 6. In the. installation shown herewith. theclearance is sufilcient. to. permit the arm 6 to move to a. vertical ption. and, thus to. carry the. damper to: the f ul1 open position.

weclaimj 1,. In combination. with a combustion apparatus having a smokepipe and a blower, a damper for saidgcombustion apparatus injlsaid pipe,and means, for automatically moving said damper, said means comprising adamper operating member providedwith movin means tending, when free todo so, to move itfin, one direction; and means for moving-it in theopposite direction, said; means2 including a, pressure responsivedevice, aconnection, member between said p essure responsive device andsaid damper moving means, a connection fromgsaidblower in, communicationwithonesideof said pressure. operated device, and a connection fromsaidsmokepip i municatiorr withthe opposite side ofzsaidpressure responsivedevice, whereby the said pressure responsive device is-caused to movethe connection member iny'one direction. as the pressure from the.blower. increases and: as the suction; in the smoke pipe increases, themoving means being effective to move the damper in, the oppositedirection as. said. Pressureand suction decrease.

2. In combination with afcombustion apparatus having? a; smoke'pipe anda blower, a damper for said combustion apparatus. insaidipipaand means;for automatically moving said damper, said means comprising a. damper.operating. member. provided. with moving means. tending; When free to.doso, 'to'finoveiitin one-direction, and means formovling it intheopposite direction, said means includin'g' a pressure. responsivedevice, a connectionv member. between. said'pressure responsivedeviceand. said. damper 'movin'g means, a connection from'said blower incommunication with one sideofsaidpress'ure operated device, and

a connection from'said smokepipe'in' communi-.

cation with the? opposite side of said; pressure responsive device,whereby'the said: pressure; responsive device is causedto move theconnection member in one directionfas the pressure from the blower.increases and as the suction-in'the smoke pipeincre'ases', the movingmeans being effective to move the damper in. the "opposite direction assaid pressure :and suction decrease, and: a stop on 3, In combinationwith a-c0mbustion appara'{ tus having a smoke-pipe and aiblow'er,aidamper for said. combustion apparatus" ihisaid pipe, and means rorautomaticallymoving s'aiddampen-said.

means comprising a damper operating member provided with moving meanstending, when free to do so, to move it in one direction, and meansfor'moving it in the opposite direction, said means including a pressureresponsive device, a connection member between said pressure responsivedevice and said damper moving means, a connec-' tion from said blower incommunication with one side of said pressure operated device, and aconnection from said smoke pipe in communication with the opposite sideof said pressure responsive device, whereby the said pressure responsivede-' vice is caused to move the connection member in one direction asthe pressure from the blower increases and as the suction in the smokepipe increases, the moving means being effective to move the damper inthe opposite direction as said pressure and suction decrease, and meansfor latching said connection in one position, said means including amember in said connection and a latching member, the two being adaptedto be engaged together, the latching member being positioned out of theline of normal travel of said connection.

4. In combination with a combustion apparatus having a smoke pipe and ablower, a damper for said combustion apparatus in said pipe, and meansfor automatically moving said damper, said means comprising a damperoperating member provided with moving means tending, when free to do so,to move it in one direction, and means for moving it in the oppositedirection, said means including a pressure responsive device, aconnection member between said pressure responsive device and saiddamper moving means, a connection from said blower in communication withone side of said pressure operated device, and a connection from saidsmoke pipe in communication with the opposite side of said pressureresponsive device, whereby the said pressure responsive device is causedto move the connection member in one direction as the pressure from theblower increases and as the suction in the smoke pipe increases, themoving means being effective to move the damper in the oppositedirection as said pressure and suction decrease, and a stop on saidconnection member effective to limit movement of said pressureresponsive device in one direction, and means for latching saidconnection in one position, said means including a member in saidconnection and a latching member, the two being adapted to be engagedtogether, the latching member being positioned out of the line of normaltravel of said connection.

5. In combination with a combustio apparatus having a smoke pipe and ablower, a damper for said combustion apparatus in said pipe, and meansfor automatically moving said damper, said means comprising a damperoperating member provided with moving means tending, when free to do so,to move it in one direction, and means for moving it in the oppositedirection, said means including a pressure responsive device, a flexibleconnection member between said pressure responsive device and saiddamper moving means, a connection from said blower in com municationwith one side of said pressure operated device, and a connection fromsaid smoke pipe in communication with the opposite side of said pressureresponsive device, whereby the said pressure responsive device is causedto move the flexible connection member in one direction as the pressurefrom the blower increases and as the suction in the smoke pipeincreases, the moving means being effective to move the damper in the 6opposite direction as said pressure and suction decrease.

6. In combination with a combustion apparatus having a smoke pipe and ablower, ,a damper for said combustion apparatus in said pipe, and meansfor automatically moving said damper, said means comprising a damperoperating member positioned outside of the smoke pipe provided withmoving means tending, when free to do so, to move it in one direction,and means for moving it in the opposite direction, said means includinga pressure responsive device, a connection member between said pressureresponsive device and said damper moving means, a connection from saidblower in communication with one side of said pressure operated device,and a connection from said smoke pipe in communication with the oppositeside of said pressure responsive device, whereby the said pressureresponsive device is caused to move the connection member in onedirection as the pressure from the blower increases and as the suctionin the smoke pipe increases, the moving means being eifective to movethe damper in the opposite direction as said pressure and suctiondecrease.

7. In combination with a combustion apparatus having a smoke pipe and ablower, a damper for said combustion apparatus in said pipe, andmeansfor automatically moving said damper, said means comprising a damperoperating member positioned outside of the smoke pipe provided withmoving means ten-ding, when free to do so, to move it in one direction,and means for moving it in the opposite direction, said meansincluding'a pressure responsive device, a connection member between saidpressure responsive device and said damper moving means, a connectionfrom said blower in communication'vvith one side of said pressureoperated device, and a connection from said. smoke pipe in communicationwith the opposite side of said pressure responsive device, whereby thesaid pressure responsive device is caused to move the connection memberin one direction as the pressure from the blower increases and as thesuction in the smoke pipe increases, the moving means being efi'ectiveto movethe damper in the opposite direction as said pressure and suctiondecrease, and a stop on .said connection member efiective to limitmovement of said pressure responsive device in one direction. 7 I g 8.In combination with a combustion apparatus having a smoke pipe and ablower, a damper for said combustion apparatus in said pipe, and meansfor automatically moving said damper, said means comprising a damperoperating member positioned outside of the smoke pipe provided withmoving means tending, when free to do so, to move it in one direction,and means for moving it in the opposite direction, said means includinga pressure responsive device, a connection member between said pressureresponsive device and said damper moving means, a connection from saidblower in communication with one side of said pressure operated device,and a connection from said smoke pipe in communication with the oppositeside of said pressure responsive device, whereby the said pressureresponsive device is caused to move the connection member in onedirection as the pressure from the blower increases and as the suctionin the smoke pipe increases, the moving means being efiective to movethe damper in the opposite direction as said pressure and suctiondecrease, and a stop on said connection member effective to limit 9. Incombination with a combustion apparatushaving a smoke pipe and; ablower; a damper for said combustion apparatus in said pipe, and meansforautomatically moving said damper, said means comprising a damper,operating member positioned outside of the smoke pipe provided withmoving means tending, when free to do so, to move it in one direction,and means for moving itin the opposite direction, said means including apressure responsive device, a flexible connection member between saidpressure responsive device and 'said damper moving means, a connectionfrom said blower in communication with one side of said pressureoperated device, and a connection from said smoke pipe in communicationwith the opposite side of said pressure responsive device, whereby thesaid pressure responsive device is caused to move the flexibleconnection member in one direction as the pressure from the blowerincreases and as the suction in the smoke pipe increases, the movingmeans being effective to move the damper in the opposite direction assaid pressure and suction decrease, and means for latching saidconnection in one position, said means including a member in saidconnection and. a latching member, the two being adapted to be engagedtogether, the latching member being positioned out of, the line ofnormal travel of said connection.

10. In combination with, a combustion apparatus having a smoke pipe andablower, a damper for said combustion apparatus in said pipe, and meansfor automatically moving said damper, said means comprising a damperoperating member positioned outside of the smoke pipe provided withmoving means tending, when free to dose, tormove it in one direction,and means for moving it in the opposite direction, said means includinga pressure responsive device, a flexible connection member between saidpressure responsive device and said damper moving means, a connectionfrom said blower in communication with one side of said pressureoperated device, and a connection from said smoke pipe in communicationwith the opposite side of said'pressure responsive device, wherebythesaid pressure responsive device is caused to move the flexibleconnection member in one direction as the pressure from the blowerincreases and as the suction in the smoke pipe increases, the

moving means being efiective to move the damper in the oppositedirection as said pressure and suction decrease, and a stop on saidconnection member effective to limitmovement of said pressure responsivedevice in one direction, and means rori atcning said connection in oneposition, said means incIudi-ng a rnerr-rber in said connection and alatching member, the two being adapted to be engaged together, thelatching member being'positioned' outof the line of normal travel ofsaid'connection.

11 In combination with a combustion apparatus having a smoke pipe and ablower, a damper for said combustion apparatus in said pipe, and meansfor automatically moving said damper, saidmeans comprising a damperoperating member provided with moving means, and tending, when free todo so, to move it in one direction, and means for moving it in the opposite direction, said means including a pressure responsive device, aconnection member between saidp'ressure responsive device and saiddamper, moving means, a connection member from said blower incommunication with said pressure responsive device, whereby the saidpressure responsive device is caused to move the connection member inone direction as pressure from the blower increases, the moving meansbeing effective to move the damper in the opposite direction as saidpressure'decreases, and means for latching said connection ini oneposition, said ,means in'cludng a member in said connection and alatching member}. the two being adapted to be engaged together, thelatching member being positioned out of the line of normal travel ofsaid connection. 7

12. In combination with a combustion appaatus having a smokepipe and ablower, a damper or said combustion apparatus located in said pipe, andmeans for automatically moving said damper in response to variations inpressure conditionslin said blower and in said smoke pipe, said meansincluding a pressure responsive device, a connection to one side of saiddevice from said blower, and a connection to the other side of devicefrom said smoke pipe, a part of said pressure responsive device beingmounted Number I Name Date 499,177 Ilhiell Jan. 1'7, 1893 1,572,277Fessenden et al. Feb. 9, 1926 1,685,787 f en son. Oct. 2, i928 PATENTSNumber Country Date Great Britain :May 16, 1935

